As an optical connector for connecting optical transmission lines to each other, ones of various forms have been proposed.
For example, the optical connectors in Patent Literature 1 and 3 have receptacles which are fastened to substrates provided with optical waveguides and plugs for holding optical fibers. Further, by fitting the plugs in the receptacles, the optical waveguides and the optical connectors are positioned (connected).
Further, for example, the optical connector in Patent Literature 2 has a first ferrule which is fastened onto the substrate provided with the optical waveguides and a second ferrule for holding the optical fibers. In the front end face of the first ferrule, engagement holes are formed. while alignment pins protrude from the front end face of the second ferrule. By fitting the alignment pins in the engagement holes, the optical waveguide and the optical connector are positioned (connected).
In the techniques of Patent Literature 1 and 3, basically the entire plug is fitted in the receptacle to connect the optical waveguide and the optical fiber. Accordingly, in order to realize high precision positioning, the entire plug must be formed with a high precision.
In the technique in Patent Literature 2, contact of any member with the alignment pins and so on causes an unforeseen external force to be applied to the alignment pins, so the alignment pins are liable to deform. As a result, high precision positioning is liable to become impossible. Further, in the technique in Patent Literature 2, the alignment pins and the engagement holes fit with each other on the substrate, therefore lowering of the profile is difficult.
Accordingly, it is desired to provide an optical connector, an optical transmission module, and a plug for optical connector capable of suitably positioning optical transmission lines relative to each other. For example, it is desired to solve at least one of the inconveniences described above.